The present invention relates to an automatic processor for a silver halide photographic light-sensitive material (hereinafter referred to simply as a light-sensitive material), and in particular, to an automatic processor for a silver halide photographic light-sensitive material wherein processing capacity at high speed is excellent, stability in continuous jetting is excellent, and neither mist nor jet failure caused by contamination of a nozzle plate is caused.
Due to a recent rapid increase of mini-lab photofinishing labs, the number of light-sensitive materials to be processed in one lab has been reduced, and a rate of replacement of processing solution in a processing tank is lowered accordingly. Therefore, a processing solution tends to be deteriorated and tends not to maintain stable processing capacity. Further, there have recently been increased demands for a mini-lab wherein maintenance such as cleaning of an equipment and daily control are not required.
Therefore, TOKKAIHEI No. 6-324455 discloses a technology wherein a processing solution for processing a silver halide photographic light-sensitive material is contained in a container (for example, an ink jet head) which is highly airtight, and the processing solution is supplied to an emulsion side through a gaseous phase.
However, the ink jet head stated above is structured to jet an extremely small droplet because it is generally required to form fine images, and an amount of solution to be supplied is established to be considerably small. Therefore, when a conventional ink jet head is used as it is, an amount of processing solution to be supplied to an emulsion side of a light-sensitive material is insufficient, and absolute insufficiency of components (for example, color developing agents) necessary to conduct processing is caused. It is therefore difficult to finish reaction in processing steps completely.
For example, even in the case of increasing the number of jet nozzles (orifices) in the ink jet described in U.S. Pat. No. 4,901,093 to realize high speed processing capacity, an amount of solution to be supplied is still insufficient, in the case of a processing solution which processes a silver halide photographic light-sensitive material, It has been found that maintenance such as cleaning of a head section is needed to maintain more stable jet, and clogging of a nozzle tends to be caused.
The technology disclosed in TOKKAIHEI 6-324455 is one to process a light-sensitive material mainly for redox amplification processing. Since an amount of coated silver of a light-sensitive material for redox amplification processing is much less than that for an ordinary light-sensitive material, even when this technology is applied to processing of an ordinary light-sensitive material which is an object of the present invention, an effect which can be obtained is no more than an insufficient effect, and this technology can not be put to practical use.
In the control valve and its control method both disclosed in the technology stated above, stable jet is difficult. Namely, there is no description of timing for opening and closing of the valve, and it can not be put to practical use for the reason of occurrence of mist.
The technology described in TOKKAIHEI 9-211832 is a technology diverted from an ink jet method of a thermal development system, and it is far from the solution of the problem of stability of continuous jet which is specific to silver halide photographic processing of the present invention.
In recent years, there has been a rapid increase in the number of mini-lab photofinishing labs, especially because of the strong demand for rapid processing. Under this situation, simple control, high speed processing and rapid processing are demanded. The ink jet head stated above, however, is structured originally to jet an extremely small droplet, and a solution necessary for reaction can not be supplied sufficiently. On the other hand, when an ink jet having plural nozzles is used for a long time under a great load (such as simultaneous jet from all nozzles), it is difficult to supply the necessary amount stably. An indispensable technology, therefore, is to increase an amount of jet for a processing solution sharply and to conduct stable jet.
It has been found newly that air bubbles tend to be mixed in a solution because processing speed for continuous processing is higher compared with an occasion of an ink jet. Namely, due to this, pressure loss in a chamber is caused and a jet failure is caused. It was also found that an air bubble generated does not get out of a chamber easily in the case of a processing solution. Compared with ordinary ink, a processing solution for photographic use has an extremely high salt concentration of inorganic salt, and thereby, air bubbles tend to be generated, which makes it difficult to solve the problem.
TOKKAIHEI No. 8-206569 discloses a method to supply a processing solution to a photographic material by the use of a spray bar. Due to this, an amount of a processing solution can be increased sharply, but it was found that generation of mist caused by mixture of air bubbles and by mixture of minute insoluble matters is a problem.